As a fellow Year 12 who debated between law and another subject (psychology), here's how I made my decision to study law:
1.
Researching universities and modules in both degrees
A Law LLB course is very different to most other degrees, as it is set up to prepare you to be a lawyer. There are modules that are about legal skills and drafting legal documents and they are
mandatory. A PPE course is a tripartite degree, so again, it's structured very differently to most degrees as you'll have to learn things from three different subjects. While there is some overlap, a lot of people describe it as taking A levels all over again, in the sense that the areas at first can seem drastically different. I do both philosophy and politics at A level, and while they have some overlap (political philosophy), for the most part they are very separate areas of knowledge. Even if you aren't entirely sure about what universities you want to apply to, I would definitely look at the top ones in both subjects to see how the courses are structured. Since you are aiming high, I'm assuming that means mostly Russell Groups or top 10 non-Russell Groups. I would suggest checking out UCL, LSE and Oxford's PPE course and comparing that with their law courses. I would say law courses are more flexible than most; since they are qualifying degrees, they don't typically require you to do a dissertation and have a very large range of modules in second and third year. PPE is also quite flexible in the sense that you're going to get optional modules from three different academic areas.
While your current grades look amazing, it's still good to be checking entry requirements. If you're looking at Oxbridge, they require aptitude tests in most subjects, and for law this would be the LNAT. The LNAT is not easy, and I believe they look for scores generally above 30, and strong performance in the essay portion. There are a few other universities that require the LNAT, but the vast majority don't. I'm not sure about PPE, but I'm assuming that the aptitude tests used at Oxbridge aren't ones used nationwide. You should be looking at GCSEs and A level requirements for both. Year 13 gets hard, so I would advise only picking universities with entry requirements you feel confident in achieving the grades for by the end of next year. If you're eligible for contextual offers, this is also something you should keep in mind.
For me, the biggest contributor to my decision to not study psychology and instead study law was the career options. I previously had wanted to become a clinical psychologist, which typically takes people 9-12 years to achieve after finishing A levels and the pay that I would be getting was about £50,000 - £85,000 working in the NHS. While that is an amazing salary, for the amount of work and hours I would have been doing as well as all the debt I'd have from having to go through further training and university, it didn't feel worth it. The only progression would have been becoming a clinical co-ordinator, but this takes decades of experience. I know that money isn't everything and many lawyers don't make that much money, for the area of law I'm interested in (commercial law), I would likely be making more money than average. There's a faster progression and more opportunities to go into different careers. After talking to people who work in a law firm, there's definitely a multitude of options, even if you don't end up wanting to be a lawyer. I met someone who was working in legal technology and did an LLB only to realise he didn't want to be a solicitor. With PPE, there are definitely a lot of routes, and that's just due to it being a tripartite degree. You could go into political journalism, policy advising or become a politician if you're interest in the politics side. For the economics side of PPE, you could 100% do some further qualifications or complete an apprenticeship to go into banking, finance or economy analysing positions. If you end up liking the philosophical aspect, you could go into research, academia or philosophical literature.
I think most you should really consider which degree you would enjoy
studying more, rather than the career path at first. If you do an LLB and change your mind, you can always do some further training and go into PPE related careers. With your current A levels, securing some sort of apprenticeship wouldn't be hard at all, provided you get good grades in them and for your degree. With PPE, as you mentioned, you could always do a conversion degree. I know a few people who have done conversion degrees and it was all down to them wanting to study a subject they enjoy more at undergraduate level and focus on their career later. Your time at university will help you navigate what you want to do career-wise anyway, so I wouldn't worry about this too much. Law firms do not care whether you've done an LLB or a conversion degree I promise you! So many people end up applying to study law out of fear firms will reject them based on their degree, but studying law at undergraduate level doesn't prepare you to be a lawyer as much as you'd think. Sure, they touch on key skills, but that knowledge can be gained by attending networking events, careers days and doing your own research. A Law LLB mainly teaches the theory of law. Your SQE will teach you how to apply all of this theory, if you want to be a solicitor. If you're still undecided, I'd really recommend attending open days and going to both subject talks. This is how you'll get a feel for whether the subject is for you.
Wishing you the best of luck in your decision!